He's a mutant in the way Spock is a mutant... or better example yet is Namor in that Thanos is a half breed. Thanos is a mutant member of the race of superhumans known as the Titanian Eternals. He possesses abilities common to the Eternals, but in some cases far beyond any other known member of his race; acquired through a combination of his mutant Eternal heritage, bionic amplification, mysticism, and the entity Death. Thanos was also born with the Deviant gene and as resembles the Deviants—the Eternals' cousin race—more than his own people.

I had to look some of that up because it had been forever since I read the practicalities of what make him a mutant but knew what Mudd meant.

[quote="Van Statten"]He's a mutant in the way Spock is a mutant... or better example yet is Namor in that Thanos is a half breed. Thanos is a mutant member of the race of superhumans known as the Titanian Eternals. He possesses abilities common to the Eternals, but in some cases far beyond any other known member of his race; acquired through a combination of his mutant Eternal heritage, bionic amplification, mysticism, and the entity Death. Thanos was also born with the Deviant gene and as resembles the Deviants—the Eternals' cousin race—more than his own people.